How will declining vaccination rates impact disease outbreaks in Louisiana?

Under Louisiana state law, children enrolled in any school within the state are required to receive immunizations against vaccine-preventable diseases, however, parents and guardians can request exemptions.

In addition to medical reasons, the state allows exemptions from vaccine requirements for religious and/or philosophical reasons, says the Louisiana Department of Health (LDH)

All requests for vaccine exemptions are granted, according to the LDH, yet higher rates of non-medical exemptions have been linked with increased disease transmission, according to Johns Hopkins Bloomberg School of Public Health.

What will happen if Louisiana loses herd immunity?

Maintaining adequate vaccination coverage is critical for establishing community protection, or herd immunity, which prevents the disease from spreading easily and helps to protect vulnerable individuals.

Ninety-five percent of a population needs to be vaccinated in order to achieve herd immunity against highly infectious diseases like measles, while 90% is required for other diseases like diphtheria.

This percentage is set by the National Center for Health Statistics’ Healthy People (HP) 2030 target, which focuses on preventing infectious diseases, according to the CDC.

The amount of children vaccinated against diphtheria, tetanus and pertussis is below the HP2030 target of 90%, with most recent data showing 85% of children in Louisiana receiving full vaccinations, according to Johns Hopkins.

The percentage of children vaccinated against measles, mumps and rubella is also below the HP2030 target of 95%, with most recent data showing 93% of children in Louisiana receiving immunizations.

A measles outbreak can indicate insufficient vaccine coverage within a population, and Louisiana reported three cases of measles in 2025. While this may seem like a low amount, even one case of measles triggers outbreak response activities as it is one of the most contagious diseases, according to Johns Hopkins.

If vaccine coverage continues to decline, outbreaks are likely to become inevitable and children will be in greater danger of severe illness and mortality, says Tulane University.

Presley Bo Tyler is a reporter for the Louisiana Deep South Connect Team for USA Today. Find her on X @PresleyTyler02 and email at PTyler@Gannett.com